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Discussion Starter #1 (Edited)
Hi Guys,
Here's my question, if one has 19 inch rims, what tire size should I use for the front? The front rim width will be 9 inches. The tires for the rear will be 285/30/19. The rear rim size will be 10 inches.
So should the front be 255/35/19 OR.....
should the front be 255/30/19 ???
When giving me your option/advise please keep in mind I have Dinan's Stage # 2 suspension, which lowered the car's overall height by approx. 3/4 inch. I don't know which tire size to pick for the front of my car. When you tell me your recomendation, please tell me why your picking the size, so I understand the reasoning.
Thank you very much for your help.
Robert
 

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I'd go 255-35

and 295-30
 

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Well, what tires?

here is my method: what is the stock size? rolling diameter of the tire as well as revs/mile

I try to get the same numbers with the new size. For the M this is 25.7 and 25.6 (front and rear) and 809 and 819 (front and rear)

Now, look at the tires you want on tirerack- look up the 'specs' tab. I try to find a tire that has a 'width range' in the middle for my size. For example, the Mich PS in the 285/30-19 had a range of 9.5 to 10.5, and the spec numbers they provide are measured from the tire on a 10 inch rim (just what you proposed) the rolling diameter is 25.8 and rev/mile is 807. Perfect.

Good luck on the fronts for a 9" wheel... you'll either be over or under...maybe 255/35??

All this assumes adequate offset and clearance- some minor sidewall geometry difference can matter when you are tight.

Anyway, this is how I've always looked at this- like to hear any other thoughts.

A
 

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Re: For those who have 19 inch rims, I need help deciding which tire size is optimal.

With a 9" front wheel, I would go with 255-35-19, this way your keeping the rolling diamter closer to stock. However, a 255mm tire on a 9" wheel may be a little narrow, perhaps bump it up to 275-30-19, which is what Dinan reccomends for their front 9" wheel.

Also, keep in mind you may experience an increase in tramlining with a 275mm front tire.

Travis
 

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Discussion Starter #6
Ard asks a very good question, I forgot to mention tire name brand......

ard said:
Well, what tires?

here is my method: what is the stock size? rolling diameter of the tire as well as revs/mile

I try to get the same numbers with the new size. For the M this is 25.7 and 25.6 (front and rear) and 809 and 819 (front and rear)

Now, look at the tires you want on tirerack- look up the 'specs' tab. I try to find a tire that has a 'width range' in the middle for my size. For example, the Mich PS in the 285/30-19 had a range of 9.5 to 10.5, and the spec numbers they provide are measured from the tire on a 10 inch rim (just what you proposed) the rolling diameter is 25.8 and rev/mile is 807. Perfect.

Good luck on the fronts for a 9" wheel... you'll either be over or under...maybe 255/35??

All this assumes adequate offset and clearance- some minor sidewall geometry difference can matter when you are tight.

Anyway, this is how I've always looked at this- like to hear any other thoughts.

A

Ard,
The tire of choice for me will be the Pilot Sport. The original version is my first choice (if I can find it at Tire Rack) and the PS2 will be second choice if the originals are no longer available in my needed size.
Thanks! :cheers:
 

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I am assuming moving to 19 inch wheels is not for performance. It might look a little nicer and ride a bit firmer and cost more for tire replacement and be more prone to curb and pot hole damage and hurt acceleration. Oh, sorry, I didn't mean to rain on your parade. It always amazes me when people think that upsizing their wheels is for performance reasons, but they do look nice.

Mark
 

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Re: For those who have 19 inch rims, I need help deciding which tire size is optimal.

MAH said:
I am assuming moving to 19 inch wheels is not for performance. It might look a little nicer and ride a bit firmer and cost more for tire replacement and be more prone to curb and pot hole damage and hurt acceleration. Oh, sorry, I didn't mean to rain on your parade. It always amazes me when people think that upsizing their wheels is for performance reasons, but they do look nice.

Mark
I agree 100%... but I wasn't going to go there. :)
 

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MAH said:
I am assuming moving to 19 inch wheels is not for performance. It might look a little nicer and ride a bit firmer and cost more for tire replacement and be more prone to curb and pot hole damage and hurt acceleration. Oh, sorry, I didn't mean to rain on your parade. It always amazes me when people think that upsizing their wheels is for performance reasons, but they do look nice.

Mark
I think the other main reason was to make sure the wheels cleared the Dinan Brembo BBK that he's got on order :typing:
 

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Discussion Starter #10
Here's my concern on the front tire size........

My current front tire size is 255 but Im not sure just how wide I can go without running into any rubbing issues with the inner fender liner, especially since the Dinan suspension lowered the height of the car by 3/4 of an inch.
Anyone??? :flag:
 

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Robert,

just as some info...the 255's should be no issue.

Im running the 275's with the ACS suspension and it has not needed to be raised at all with it.

going only 10mil wider should not affect anything even thought the suspension is slightly lowered.


Give me a call if you wanna talk about it.
 

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Re: For those who have 19 inch rims, I need help deciding which tire size is optimal.

MAH,

I think you would be hard pressed to notice a performance difference if one were to buy a high quality, relatively lightweight 19" wheel. Were talking about a 400hp, 3900lb sedan, not a Lotus Elise. Also, there are several companies out there that make very strong forged wheels, so unless your driving really horrible roads, wheel damage shouldn't be a huge issue. As far as pricing goes, you've got me there. Selling your OEM wheels would help a lot though, as they usually fetch atleast $1,300.

The OEM M5 wheels have proven to be of good quality and decent weight, and personally I like the more stealth look. But a good quality 19" wheel is also great.

Travis
 

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Re: Here's a question for Rob and other tire/rim experts..........

FAST 5 said:
Will i be able to mount 275 tires onto a 9 inch rim or is the 9 inch rim considered too narrow??? Would i require a 91/2 inch rim???
Thank you! :)
I have 275's on my front dinan wheels which are 9" in diameter.
 

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I also have 275's up front on a 19 inch HRE rim



Regards,


Marion
 

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Rob

My car is stock height?
Try and measure the diameter of the inner wheel well, compared to the diameter of the new tires.
I personally don't think it would rub however it may effect your ride.

Regards,

Marion
FAST 5 said:
Yea.. but Marion, Do you have the stock suspension or did you changed & lower your car's suspension???
Thanks.
Robert
 

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Discussion Starter #20
SC'dKellenersM5 said:
all issues settled now robert?

Yes, they are Rob. Thanks for your input and information you gathered from RENNSPORT (Sam). So, the verdict is Pilot Sport II tires with 285/30/19 on the rear rims and 265/30/19 on the front rims. Im a bit gun shy to do the 275 size for the front. What do you think??? I figure, I should play it afe with the 265s.
Robert :cheers:
 
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